Septic Arthritis

When there is an infection in the joints, which is very painful as well, it is referred to as septic arthritis. It can be caused by the germs from other parts of the body, infecting the joints, or entry of germs in the joint due to penetrating injury.

The most commonly infection joints are knee and hip joints and it usually affects infants and older adults. It is crucial to get immediate medical treatment as septic arthritis is known to severely damage the cartilage and bone in the joint. The joint is drained by using a needle or by performing surgery. Antibiotics are given intravenously to stop the infection if required.

What Are the Symptoms of Septic Arthritis?

Symptoms of septic arthritis depend on the age of the person and also the medication the person is taking. Some of the commonly seen symptoms are:

Swelling in the joints

Feeling warm around the joint and redness

Severe pain during movement of the joint

Fever, fatigue and chills

Weakness, irritability and decreased appetite

Rapid heartbeat

When to See a Doctor

If you experience sudden and severe pain in the joints, it should be checked by a doctor, as immediate treatment can prevent major damage to the joints.

What Are the Causes & Risk Factors of Septic Arthritis?

Bacteria from other parts of the body can cause septic arthritis by travelling through the blood stream. It is also possible that open wounds or surgical openings get infected by bacteria, e.g. knee surgery. The bacteria responsible for causing septic arthritis are Haemophilus influenza, staphylococcus and streptococcus. Once in the bloodstream, they can infect the joint and cause pain and inflammation.

Viruses also cause septic arthritis, the most common ones are:

Hepatitis A, B & C Virus

Herpes viruses

HIV

Parvovirus B19, HTLV-1

Adenovirus, Coxsackie virus and Mumps virus

Fungi are also known to be responsible for septic arthritis. They are Histoplasma, Coccidiomyces and Blastomyces. The infection causes by these are less severe than the ones caused by bacteria.

Risk Factors

The Risk factors for developing septic arthritis are given below.

Risk Factors

Description

Existing Joint Problems

If you suffer from osteoarthritis, rheumatoid arthritis, gout, lupus or have undergone joint replacement surgery, any joint surgery or have joint injury, you are at more risk to develop septic arthritis

On Medication for Rheumatoid Arthritis

The medications of rheumatoid arthritis suppress the immune system, which increases the susceptibility for septic arthritis. Also it is difficult to diagnose in patients with RA, since the signs and symptoms are very similar.

Skin Fragility

People whose skin bruises or breaks easily and does not heal quickly, give access to bacteria. This is seen in people suffering from psoriasis and eczema. Skin wounds, puncture sites from injections are also prone to infections.

Weakened Immune System

Since the immune system is weak, it becomes difficult for the body to fight off any infection. People taking immune suppressants or those suffering from kidney disease, liver problems or diabetes are at an increased risk of infection.

How Is Septic Arthritis Diagnosed?

The diagnosis begins with a physical examination of the joint and history of the signs and symptoms. To confirm septic arthritis, tests need to be done.

Arthrocentesis is a test which involves testing the synovial fluid from the infected joint and checking it for color, consistency, WBC and bacterial presence.

A blood test can also be done to determine the WBC count and the presence of bacteria and the type of bacteria.

Imaging tests like X-ray, MRI, CT-scans and nuclear scans are helpful in determining the damage to the joints caused due to the infection.

What Are the Treatments for Septic Arthritis?

Various treatments are available for Septic Arthritis. Given below are some of the most commonly prescribed treatments.

Antibiotics. The first mode of treatment is injecting wide spectrum antibiotics in the vein, which can kill the bacteria associated with septic arthritis. The dosage is usually high to ensure that the bacteria are destroyed. Once the reports from tests are available, the type of antibiotics used will be specific to the bacteria causing the infection. Although the symptoms disappear on taking the antibiotics, they need to be taken for a stipulated amount of time to ensure the infection is completely gone.

Removing the joint fluid. The infected fluid is drained out from the joints to ensure that it does not cause damage to the joint. It also helps the antibiotics to act on the infection. The draining is simpler when smaller joints like knee or elbow are involved. However, a small surgery might be required for hip joints. Sometimes, the fluid will be required to be drained multiple times till the accumulation of infected fluid does stop.

Splints. Since the infection causes severe pain in movements, the joint is usually splinted initially.

Physiotherapy. After the infection has been cured, the joint can become stiff over a period of time, due to lack of activity. Physiotherapy will be helpful in ensuring that the movement is maintained in the joint.

Artificial joints. Incase artificial joints get infected, they are removed and new joints are inserted.